My 2005 Jetta TDI Wagon started making a "spring like sound" that was coming from the right rear corner - I pulled the wheel and found this:

I'm trying to decide if I need to "ground" the car or if it can be safely driven while I wait for parts to arrive. I figure I should replace both springs, their bumpers, and since I'm there also replace the shocks (they are probably original with 200,000+ miles on them).

Given the mileage - and the work it will take to replace the spring - is there anything else that I should be looking at / replacing? I assume it would be wisest to replace both springs.

You are right to replace the shocks as well, if the spring is broken the shock will be bearing far more weight than it's designed for.
– GdDFeb 3 at 10:26

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@GdD Shocks don't bear weight, they just add resistance to movement. As long as the suspension rubber buffers are intact which limit suspension maximum travel, then there should no damage to the shocks.
– HandyHowieFeb 3 at 11:25

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I don't quite agree with that @HandyHowie, the shocks don't bear weight in normal circumstances, but a broken spring isn't normal. Replacing the shocks is a good call.
– GdDFeb 3 at 11:27

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The failure is hydrogen stress cracking ; could be caused by coating failure permitting corrosion, but more likely a manufacturing defect in the steel which concentrated stresses and hydrogen. I would replace both rear springs. It has nothing to do with the shocks but because of the mileage , I would replace the shocks at the same time.
– blacksmith37Feb 3 at 15:41

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@dlu If nothing else looks damaged, I wouldn’t do anything else. It does look like it would be a simple job to remove the shocks, so if I was doing the job I would probably test the shocks off the car make sure they are working and if ok, I would put them back on.
– HandyHowieFeb 3 at 18:35

The basic issue from a mechanical point of view is that the spring (not the shock!) is what supports the weight of that corner of the car. Clearly, with a piece missing, it is not doing that as it was designed to.

If the car "bounces" while being driven, the broken spring may end up further out of position and not carrying any load at all.

Personally I wouldn't drive it anywhere at more than walking pace, and avoid anything like driving up and down a kerb.

The last three quarters of a turn of the spring is flat, and coiled to a smaller diameter than the body of the spring, so that it can sit snugly around the locating nub welded onto the frame, with the rubber isolator between them. With most of the last turn missing, the spring is effectively resting on a single point. The first picture shows its proper position - you can just see a rusty circle behind the isolator that has also rolled out of position. Were the spring and isolator on that pad before you lifted it? You probably can't tell now, but the risk is that the spring becomes free to move out of position, and potentially fall out, or worse, fall towards the tire and rip it. Tyipcally, the limit of extension of the shock is intended to make sure that the spring doesn't come loose even under full travel, there's no guarantee of that now.

Al that was preventing the spring from moving any further was the now larger next coil of the spring, which was probably rubbing against the nub, and producing the sound you heard. You'd likely be challenged to even lower the car back onto its suspension with the spring returning to its proper location, but there's no guarantee it'd stay there.

I'd park that vehicle until you can get a new spring. It's just not worth the risk of using it.